Spine - Spine is 2D animation software designed specifically for software and game development.
IcoFX - IcoFX is an all-in-one solution for icon creation, extraction and editing.
Synfig Studio - Just another WordPress site
Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
DragonBones - DragonBones is an open source project for 2D skeletal animation.
VistaCreate - The VistaCreate is a free and global digital platform which is known for sharing, searching, finding, and creating great art.